Forced-draft apparatus.



?ATENTE D SEPT. 29,1903.-

.11. c. PBABDDY." FORGED DRAFT APPARATUS.

APPLICATION FILED JULY 19. 1901.

no MODEL.

r m m Witnesses Fatented September 29, 1903.

PATENT OFFICE.

ROYAL c. PEABODY, on BROOKLYN, NEW YORK.

FORCED-DRAFT APPARATUS.

srnormcn'rzon forming part of Letters Patent No. 740,370, dated September 29, 1903.-

Original application filed March 3, 1901, Serial No. 50.921. Divided and this application filed July 19, 1901. serial N0.68,926. (No model.)

To all whom it may concern.-

Be it known that I, RO AL C. PEABODY, a citizen of the United States, residing in the borough of Brooklyn, city of New York, State of New York, have invented a new and usef 111 Improvement in Forced-D raft Apparatus, of which the following is a specification.

My invention relates to improved forceddraft apparatus for use in connection with fire-boxes.

For the sake of illustration I will describe my invention as .applied to a fire box of the type described and claimed in my application for Letters Patent, filed March 13, 1901, Serial No. 50,921, of which the present application is a division.

My object is to provide means by which the fuel in a fire-boirwill be supplied with the necessary air for combustion in a simple, cheap, and effective manner.

In order that the invention may be better understood, attention is directed to the accompanying drawings, forming a part of this specification, and in which Figure l is a longitudinal section of a boilerof combustion pass along the nest of tubes to the smoke-pipe 2, which is preferably provided with an inclosing jacket 3, communi eating with the atmosphere, as is common The front of said furnace is provided with the usual swingingdoors (not shown) normally closed, but which may be opened for hand-stoking when desired, and with an ashpit door (not shown).which may be opened or removed for cleaning out the ash-pit. Mounted within the fire-box l is a wind-box 4, formed of vertical boiler iron walls, and mounted above the wind-box, to form the top thereof, is the first of a series of rotary perforated tubular grate-bars 5, made of refractory material. Leading into the wind-box 4 is a blast-injector casing 6, having a series of bell-mouths Z therein and connected at its 'sumed in the furnace.

having valves 11 therein and which connect with a nozzle 12, having a cap 13, which contracts the entrance'to the outermost bellmouth, as shown. The exhaust-steam pipe 10 may be supplied from a motor 14: for driving an automatic underfeed stoker, if used, or from any other source.

In operation the fuel is fed to the gratebar 5 by the automatic stoker or by any other means and by the rotation of said grate-bar to the next, and so on. Combustion having started, the fuel in its passage from one gratebar to another will be consumed, until at the farthermost grate-bar it will have been reduced to ash or clinker. To increase the combustion, live or exhaust steam is admitted to the injector, and in passing through the several bell-mouths into the wind-box a powerful suction will be created, drawing air downwardly around the smoke-pipe in a heated condition and blowing it into the wind-box, from which it passes up through the gratebar 5. If desired, a blast may be also directed into the ash-pit, so as to pass up through the grate. By thus blowing a blast of heated air in the furnace the combustion will be very intense, while the heat of the air will tend to disintegrate or vaporize any oil which may be mechanically entrained with the steam and which will be effectively con- Having now described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is as follows:

The combination witha furnace, of a steamblast injector connected therewith below the grate-bars and comprising a plurality of bellmouths, with a steam-nozzle opening into said mouths, means for supplying live and exhaust steam to said nozzle, and a cap carried by said nozzle for contracting the bellmouth with which it immediately codperates, substantially as set forth.

This specification signed and witnessed this 9th day of July, 1901.

ROYAL O. PEABODY.

Witnesses:

Gno. H. FULLERTON,

D. BRowER, J r. 

